Copper wires could become Nanotech batteries

Researchers at the University of Central Florida believe they have discovered a way of storing energy using copper wires that could lead to smaller electronics, lighter hybrid cars or aircraft and even be used in clothing to recharge mobile devices.

Imagine being able to carry all the juice you needed to power your MP3 player, smartphone and electric car in the fabric of your jacket?

Sounds like science fiction, but it may become a reality thanks to breakthrough technology developed at a University of Central Florida research lab.

So far electrical cables are used only to transmit electricity. However, nanotechnology scientist and professor Jayan Thomas and his Ph.D. student Zenan Yu have developed a way to both transmit and store electricity in a single lightweight copper wire.

Their work is the focus of the cover story of the June 30 issue of the material science journal Advanced Materials and science magazine Nature has published a detailed discussion about this technology in the current issue.

“It’s an interesting idea,” Thomas said. “When we did it and started talking about it, everyone we talked to said, ‘Hmm, never thought of that. It’s unique.’”

Copper wire is the starting point but eventually, Thomas said, as the technology improves, special fibers could also be developed with nanostructures to conduct and store energy.

More immediate applications could be seen in the design and development of electrical vehicles, space-launch vehicles and portable electronic devices. By being able to store and conduct energy on the same wire, heavy, space-consuming batteries could become a thing of the past. It is possible to further miniaturize the electronic devices or the space that has been previously used for batteries could be used for other purposes. In the case of launch vehicles, that could potentially lighten the load, making launches less costly, Thomas said.

How everything was created and how it works

Thomas and his team began with a single copper wire. Then he placed a sheath over the wire made up of nanowhiskers the team grew on the outer surface of the copper wire. These whiskers were then treated with a special alloy, which created an electrode. Two electrodes are needed for the powerful energy storage. So they had to figure out a way to create a second electrode.

They did it by adding a thin plastic sheet around the whiskers and wrapping it around using a metal sheath after generating nanowhiskers on (the second electrode and outer covering). The layers were then glued together with a special gel. Because of the insulation, the inner copper wire retains its ability to channel energy, but the layers around the wire independently store powerful energy.

In other words, Thomas and his team created a supercapacitor on the outside of the copper wire. Supercapcitors store powerful energy, like that needed to start a vehicle or heavy-construction equipment.

How this technology could be used for electric vehicles?

Well, this breakthrough could be embedded almost everywhere and hybrid and electric cars are not exclusions.

For instance, when we talk about hybrids, you could use this technology to replace high energy-density supercapacitors, sometimes mistaken by hybrid car owners as a second battery, which provide the quick shot of energy that cars and heavy machinery need to start.

"You open your trunk and you see a lot of space is taken by your batteries. If you can just use some of the cables along the length of your car, you don't need any of that space for batteries," Thomas said.

Transferable technique

Although more work needs to be done, Thomas said the technique should be transferable to other types of materials. That could lead to specially treated clothing fibers being able to hold enough power for big tasks. For example, if flexible solar cells and these fibers were used in tandem to make a jacket, it could be used independently to power electronic gadgets and other devices.

“It’s very exciting,” Thomas said. “We take it step by step. I love getting to the lab everyday, and seeing what we can come up with next. Sometimes things don’t work out, but even those failures teach us a lot of things.”

Yu is the co-author of the study. He works in Thomas’ Nano Energy-Photonics Group. It conducts research focused primarily on nanostructured supercapacitors and Lithiuim-ion batteries, nanoarchitectured light-trapping solar cells, photorefractive polymers for 3D display applications, and nonlinear optical materials.

Thomas is a faculty member at the UCF Nanoscience Technology Center with joint appointments in the College of Optics and Photonics (CREOL) and the College of Engineering and Computer Science. He has multiple degrees including a master’s degree in chemistry and a Ph.D. in material science. He is a recipient of National Science Foundation’s prestigious CAREER award. He’s received media attention over the past few years for his work on lasers and advanced nanomaterials.